


Marceline the Wizarding Queen

by narglesoup



Category: Adventure Time, Harry Potter - J. K. Rowling
Genre: Alternate Universe, Alternate Universe - Hogwarts, Crossover, F/F, Post - Deathly Hallows, Teen Angst
Language: English
Status: In-Progress
Published: 2013-04-20
Updated: 2013-05-27
Packaged: 2017-12-09 01:00:32
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,878
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/768145
Author URL: https://archiveofourown.org/users/narglesoup/pseuds/narglesoup
Summary: <blockquote class="userstuff">
              <p>Far away in the middle of nowhere, lives an unsuspecting vampire with no idea that she is about to go on an amazing adventure. After not having much of a childhood herself she is given a chance to go to a famous 'mortal' school, like a normal girl. But of course, it's not as straightforward as that.</p>
            </blockquote>





	1. The Beginning

**Notes for the Chapter:**

> A/N: based upon Harry Potter and Adventure time (both things I do not own) .... this is my first fanfic and I'm hoping to make this pretty long (if all goes well) This is the first chapter, enjoy (:

Far away from any civilisation, on the top of a great hill where the closest village is miles away, sits an old abandoned looking house, crumbling from its foundations. The garden is large and overgrown, stretching for miles until it just blends into the landscape. You wouldn’t expect people to be living in there.

Inside, a teenage vampire listens to the radio, quietly humming along to the tunes that play. The snores of an old man drift into the room through the walls of the old house adding to the calm. It was the middle of the day yet Marceline didn’t have the heart to wake him. She floats to the fridge in search of something to eat, but alas, nothing worth her time. She looked outside, noticing an old looking cat sitting on the garden fence. It had strange markings around the eyes and looked like it was watching her. The cat jumped down and wandered off. Odd cat.

She sighs, floating back to the living room, ignoring the grumbles of her stomach. She’d leave the house herself, but it was a sunny day and didn’t want to take the risk of her skin burning. As the sound of another track died down she heard a screech from outside and then the flapping of the letterbox, Marceline raised her eyebrows in surprise, unused to letters. She went to the door and picked up the letter. She stood, admiring the red seal for a moment, which was imprinted with a capital ‘H’. The front read:

_Miss Marceline Abadeer_

_The biggest room_

_Old house on the Hill_

_The Peak district_

 

She opened the letter, muttering the words as she read them, “pleased to inform…Hogwarts …school of witchcraft and wizardry…” Underneath read:

_Due to your special circumstances you shall be escorted to Hogwarts by me personally. Expect to be collected from your home on the evening of Saturday, 30 th of July._

_Yours sincerely,_

_Minerva McGonagall_

_Headmistress_

Marceline shrugged. ‘Seems legit’ she mumbled before absently drinking the red out of the seal.

* * *

 

The night of the 30th happened to be that very same day. Marceline began rushing about the house, preparing herself for the trip. She realised she didn’t have any of the things on the list of supplies, but that didn’t bother her. She was going to school! Finally she’d be like a normal mortal, she thought. It was something she’d always dreamed of.

She found an old battered trunk in the loft, black on the outside, but on the inside a beautiful rich red. Her stomach grumbled but she vowed never to drink it no matter how hungry she became.  She took it to her room where she began to fling her clothes inside, she had a couple of black cloaks which she considered might do as a uniform. She decided to wear her favourite black leather boots for the trip and packed some of her sandals just in case, alongside a pair of heels that were her mums that she had kept for sentiment, but had never worn herself. She took extra care packing her oldest teddy, Hambo, a gift from Simon from when he still had his memories intact. It was old and a sluggish brown now, but she made sure there was space in the trunk for it.

She hurried about the house, making sure it was clean for Simon, and with the last contents of the fridge (two slightly green eggs and questionable mushrooms) she managed to make a slightly off-smelling omelette, which she carried with her to the other room. Opening the greyed door she walked in, and found Simon already sat up in bed, beaming at her.

“Ah, Gunter!” He exclaimed, beaming, “Come up to see me have you at last?”

Marceline’s insides scrunched up when he said that, “No…it’s me, Marceline…do you remember?”

“Of course I remember you Gunter!” His eyes fell to the omelette that Marceline had thoughtfully prepared; he snatched it from her hands and began to guzzle it down. “This is way better than that crap that Vampire girl used to make.”

Marceline sighed and sat at the end of the bed, “listen, Simon. It looks like I’m going to be going away for a while. You’ll have to start looking after yourself.”

“Of course I can look after myself, I’m the Ice King!” The man was clearly deluded. Marceline swallowed, a lump in her throat forming. “Just tell me you’ll me ok? Please?” She blinked several times, forcing herself not to cry. “I’ll write.”

“Yes, yes, just leave me alone now. An old man needs his privacy!”

Marceline closed her eyes as tears began to escape, cursing herself for being so sentimental. She leant forward and kissed the old man on the forehead. Then, without a word she left the room.

After closing the door behind her she found that she could no longer hold it in. She crumpled to the floor and began to sob in silence. The tears were hot and sticky and splashed off the cold tiles as she wept. Then after a good 10 minutes she found herself again, she slashed some cold water in her face and carried on packing.

The family axe was the only thing left, so she went to her room to get it. Her bedroom wasn’t much. Her bedsheets were black to block out enough sunlight for her to rest. The walls that had originally been a soft baby pink now were a pasty white, the colour drained over the years when Marceline had drank the pigment out of hunger, leaving the walls a pasty white. They had been since filled with posters of her favourite bands, making the room look dark, but to Marceline it felt comfy, it was her space, her place to escape from life. She grabbed her bass axe from the corner of the room, the instrument she had made herself from the family axe, and had taught herself to play. She strummed a few chords and sang,

“Goodbye old room /and the memories you hold / you were my only home / I will miss you;

Mr Simon I love you / but it’s time to go / things are going to change / because that’s what people do”

Downstairs she heard a knocking at the door; she took one last look around the walls, air-kissing her posters goodbye. She floated downstairs with her trunk and bass, laying them down before opening the door.

“Good evening Miss Abadeer”

Marceline stared. Standing outside her door stood too figures. The one that spoke was a rather stern looking old woman, wearing glasses and an emerald cloak, her hair scraped back into a bun. Behind her stood a much younger, jollier man, who looked like he was trying to look stern, but failed miserably, breaking into a sort of half grin. As he did so his brown hair seemed to lighten in colour, but Marceline put that down to the lighting, as the sun was just beginning to set.

“I’m your new headmistress, professor McGonagall,” she shook her hand, “And with me is professor Lupin, who will be the new defence against the dark arts teacher. He has had special training from Mr Potter himself.” Lupin diverted his eyes at this, resigning himself to looking at the door frame with avid interest.

McGonagall looked at her sternly, leaving Marceline to wonder if she had done anything wrong. “I’m sure you won’t be any trouble, but before we allow you into Hogwarts we first need to evaluate the risks.”

“Is this because I’m a vampire?”

McGonagall sniffed, “I’m afraid so.”

Marceline nodded. She knew it wouldn’t be that straightforward. Her dreams of going to school were quickly being smashed. Of course they wouldn’t want a vampire amongst the mortal children! I’m bad, and dangerous.

She led them through into the living room. McGonagall and Lupin sat down whilst Marceline hovered just above her seat, acting cool.

Then McGonagall spoke. “Just so you know, I’ve been following you around for about a week now. I have seen no reason not to let you come to Hogwarts. However, before I can make any decisions I first need a second opinion from my colleague here.”

Professor Lupin sat forward, clearing his throat, “Ok, Marceline Abadeer. As we have gathered, you are a thousand year old vampire-half-demon, physical appearance of an 18 year old girl, black hair, red eyes.” Marceline nodded. “McGonagall has witnessed that you do not drink blood, but the colour red. You’ve cared for an elderly wizard for quite some time…with no thanks, as we have witnessed.” Marceline swallowed, was Simon an actual wizard? There are so many things he hadn’t told her, “…and you seem eager to come to school.” He turned to the older professor, “She’s passed my test. And I think it’s only right that she should get this chance. My father would have wanted this.”

McGonagall nodded, and pulled out a letter. “I think you should read this dear.” She spoke slightly kinder this time, passing Marceline the letter.

It was addressed to Hogwarts.

_Dear whoever it may concern,_

_I am writing to ask if you would accept my young friend and companion, Marceline Abadeer, as a student of Hogwarts, just as I was._

_This is my last will, I am not sure if or when I will ever be sane again, but I’m telling you that right now, I am sane. She may be a vampire, yes, but it’s all she deserves. I know she has magic too. She has stood by me though my worst psychotic episodes but now I think she needs to get her own life, and go her own way._

_I can feel myself slipping away again, please consider this offer.  You will not regret it._

_Sincerely, Simon Petrikov._

Marceline bit her lip as she read it, feeling the lump forming again. “We received this letter a couple of weeks ago, you can keep it if you want.” She nodded, not saying anything.

The sun had completely set outside now.

“One final thing,” said McGonagall, pulling out a stick which Marceline assumed to be her wand, “We need to make you look like a student.”

Marceline frowned, “Look like a – ? ”

The professor began to transfigure the vampire, changing her eyes to green instead of red, shortening her fangs, making her ears less pointy. “Now these are just cosmetic adjustments. But we’ll need to change your physical age too, which will make you look like an 11 year old rather than 18 year old." McGonagall began chanting under her breath, "You'll need to take this potion too, in order to make these changes last longer" Marceline dutifully swallowed the purple potion. 

"Good. Now, these changes will wear off over time, making you to appear to grow slightly each year, just like an ordinary student, the perfect charm.” The professor smiled now, enjoying using this advanced and complicated magic. “This is so you can fit in more easily, you can have the proper Hogwarts experience, just so long as no one knows your true identity.” Marceline wasn’t sure about this, being herself is what she’s all about. “You may find you begin to act like a younger child, but that should slowly wear off too.”

Marceline felt her body shrink, she felt her face and ears, wishing she could look in a mirror to see what she looked like. She also felt a sudden urge to play with dolls, play on swings… and smiled when she remembered she had packed her teddy. The professor also waved her wand at the suitcase, making sure that all her clothes would still fit.

“So…um… what about my equipment? I need all those books and things on the list.”

“We’re going to take you late night shopping.” Said professor Lupin with a grin, “Mr Petrikov left you some money too.”

* * *

 

They travelled in professor Lupin’s flying car. An invention, explained Lupin, which had once been illegal, but had now become quite fashionable amongst wizards and witches who wanted to blend in to both muggle and wizarding worlds. Marceline listened, not quite understanding, but so excited to be part of something.

After a few hours they had been to Gringotts and bought all Marceline’s school supplies. McGonagall became tired quickly, so they decided to stay the night at the Leaky cauldron, before heading back to Hogwarts in the morning. They each had separate rooms of course. Marceline couldn’t sleep, so decided to talk to some people walking about late in the night, and was surprised at how people treated her differently now that she looked like a young human girl.

She sat at a table in the bar swinging her legs, sipping some strawberry juice happily. She had considered red wine but realised that might not have gone down too well with the bar tender. She watched as professor Lupin came and sat down with her at the table.

“Your hair changed colour again.” Marceline stated. The man’s hair was now an unnatural orange colour. “I noticed it before, it keeps changing.”

Professor Lupin smiled, “Yeah, I was trying to keep it normal looking before, but I’m more comfortable with bright colours.” Marceline grinned, “Well it looks awesome.”

“Thanks.”

“So, I guess Hogwarts isn’t a normal mortal school is it?”

“No, it’s a school for people with magical ability. You’ll learn all about magic and how to control it. Luckily for you, you’ve got both magic and vampirism, it’s like double magic.”

“But my dad’s not magic, he’s a demon.”

“Well, maybe your mum was.”

“I don’t really know much about her. I know she was mortal.” Marceline thought for a while, “So…if I had magic, why didn’t I go to Hogwarts earlier? I’m like a thousand years old.”

“Wizards haven’t always been open-minded. Vampires and werewolves are often discriminated against, even now.”

“So that’s why I have to go undercover I guess.” Professor Lupin nodded. “What if I don’t fit in?” Marceline was suddenly worried, after all she had never really had friends besides Simon, and she didn’t really get along with the ‘friends’ her dad had picked out for her.

“Don’t worry about it. You’ll find some good friends eventually, just be yousel- … um…”

“Be myself as much as possible, without giving away that I’m a vampire. Got it.” She yawned, “woah, children’s bodies get tired quickly don’t they?” She said goodnight to Lupin, making her way back to her room. She flopped on the bed and slept the deepest sleep she had slept for years.

**Notes for the Chapter:**

> The fanfic is set in the next generation, imagine Teddy Lupin to be around 20 years. McGonagall is sort of Dumbledore's age when he was the Head. Please comment and tell me what you think. Thanks for reading! - Stephanie


	2. The Creep

**Notes for the Chapter:**

> A/N: Characters are not mine but the plot kinda is. TRIGGER WARNING: parts of this may make you feel uncomfortable and want to punch certain characters in the nuts. (dontworryitsokintheendenjoy)

Marceline woke the next day to the sheer brightness of the light outside, for the cleaning maid had walked in and opened the curtains.

“Rise and shine- aah!!”

After much hissing from Marceline the curtains were closed and the poor woman ran from the room. Marceline was not a morning person.

At breakfast (aka 2PM), Professor Lupin told Marceline that Professor McGonagall had had to leave early as she had important matters to attend to, and that they would be joining the other students in Hogsmeade ready for the boat journey across the great lake. Marceline was getting slightly annoyed at this special treatment, but she let it slide because she knew they were only trying to help, and she didn’t want to risk being kicked out before she even started.

Lupin then left to do some business, leaving Marceline to have a look through some of her new books. She was intrigued at the Defence against the Dark arts book, which this year seemed to specialise in dangerous magical animals, including Vampires. Marceline was surprised and slightly annoyed at some of the misconceptions, hopefully she’d be able to put them straight soon enough.

* * *

 

At 7PM, they left the Leaky Cauldron by floo powder, destination: the Hogs Head Inn. An extremely old wizard behind the counter nodded at Lupin, before narrowing his eyes at Marceline over his half-moon spectacles. His gaze made Marceline feel uncomfortable.

They soon caught up with the rest of the children as they were getting off the train. Marceline waved briefly at Professor Lupin before joining the group of first years that had gathered in front of a giant, bearded man.

Marceline was having a difficult time finding someone to share a boat, until she came across one with only one boy occupying it.

“Mind if I join you?”

The boy looked Marceline up and down, and nodded his head. His hair was a floppy blond Mohawk.

Marceline gingerly sat down next to him, finding the seat slightly uncomfortable, but remembered to sit and not to float like she usually would.

The boy looked at her, “So what’s your name?”

“Oh, uhm… Marceline.”

The boy laughed, “What kind of name is that?”

Marceline said nothing.

“Family name?”

“Abadeer.”

He laughed again. Marceline kept her eyes fixed on the castle approaching, considering it a waste of her time to ask the same.

* * *

 

Marceline was the first to be sorted: Slytherin. She sat down at the green table where she was coldly welcomed. She watched semi-interestedly as the rest of the first years were sorted, eyes falling on one girl with bubblegum-pink hair. It looked beautiful. Marceline sighed as the girl, Bonnibel Bubblegum, was sorted to Ravenclaw. She then rolled her eyes when the Mohawk guy, whose name turned out to be Ash, was sorted into Slytherin, and came to sit next to her.

The feast turned out to be enjoyable enough; Marceline piled up her plate with anything red, and carefully made sure no one noticed her odd eating habits. She grimaced at the way Ash ate; he used too much tongue and made too many slurping sounds. He resembled a slug in a way.

Lessons started the next day, in which Marceline participated eagerly – although for some lessons she would have sit at the back with the curtains drawn. She was glad that no one ever thought to bring this odd behaviour up. However, she’d occasionally look around the room to find Ash looking back at her, watching carefully. Every time she would awkwardly smile and look back to the front, pretending she couldn’t see him still staring in the corner of her eye.

At night, when the castle was asleep, Marceline would slip out of bed and float out of the nearest window. She loved flying up to the highest turret, whilst the castle was asleep, and lie on the roof, gazing at the swirling stars. It was chilly but that’s what she enjoyed. It made her feel alive. There she would lay in the silence, listening intently for any sounds.  She would alternate between Ravenclaw and Gryffindor tower, finding that Ravenclaw to be the quietest by far.

One night, when Marceline was on her way up the tower, she spotted the pink haired girl, Bonnibel Bubblegum. The girl was standing on the balcony looking through a telescope. She wondered for a moment if she had spotted her, but due to the lack of reaction it seemed not. Marceline sighed with relief, realising she would have to be a bit more careful when she snuck out in future. The Vampire flew the other way round to the top of the tower, before landing on the roof and quietly peeking at the other girl from above. Bubblegum was taking notes of her observations in a small notebook. It looked like really advanced Astronomy, nothing like what they were currently studying at all. Seeing Bonnibel Bubblegum on that balcony became a regular occurrence, and even though they never talked, and even though the other girl was completely unaware of her presence, it made Marceline feel slightly less alone.

* * *

 

The next day, Ash caught up with Marceline in the corridor.

“Hey M!” He said all smiles.

Marceline frowned, not liking his ‘nickname’.  “What do you want?”                

“Oh! Uhm, well I thought, you know, at the beginning of the year we got off on the wrong foot. Do you want to be friends?”

“Wrong foot? You laughed at my name and you’re just … annoying. Leave me alone please.” said Marceline, quickening her pace.

“But M, I’ll change, really. Let’s just hang out ok?” He fake-pouted, irritating Marceline further.

Marceline regarded him for a second. She might as well try, seeing as she didn’t have any other friends. “Fine.” She sighed.

* * *

 

Before she knew it, Marceline was spending most of her time with Ash, walking to lessons together, hanging out in the common room and even sitting next to each other in class. Marceline hated every moment of it, but struggled to find any specific reason to dislike Ash, as after his apology it looked like he had really changed. He was nice and didn’t laugh at her.

It was getting close to Christmas, so Marceline could go outside more often during the day. Ash suggested that they both go for a walk and she agreed. Marceline was feeling like it was going to be a good day today, the sun was low and the grass was crunchy under their feet. Ash was talking less about himself than usual, which was good. He even offered her some of his sweets, which they shared as they walked.

Marceline couldn’t figure it out, maybe he was a good friend after all, maybe it was just first day nerves, maybe –

The good feeling dropped as they reached the edge of the forest. Ash stopped and turned to face Marceline.

“Ash? I don’t think we should –  ”

Ash grabbed Marceline’s arm in a firm grip. “I’m not going to beat around the bush Marceline, I like you.” Said Ash, looking her square in the eyes with a look she hadn’t seen before. Marceline gasped in shock. She tried to gently pull away but Ash resisted, gripping tighter. She looked around frantically for the sight of any professors or students but they had gone too far away from the castle. “Ash… what are you doing?” she said, trying to keep her voice level.

“I like you Marceline, and I know you do too”

“No, I don’t. You’re hurting me.” She eyed the snail-like tongue that was getting uncomfortably near her face.

“But, sweetie…” Ash moved in, nails digging in, holding her against a tree, his other hand went to her face, bony fingers slowly moving down her neck –

That was it, the demon inside of her snapped, causing Marceline's skin to boil, her eyes burned red, she hissed, slapping him on the face and kicking him to the ground with a strength that shouldn’t belong to an 11 year old girl.

She bent down next to his whimpering body, hair wild, and sneered “ _I will never date you_.”

And then she took off, running fast, tears streaming down her face. How could someone do this? She didn’t want anyone to see her cry. So without a second thought she flew to the Ravenclaw tower balcony. She was surprised to find she was shaking; she looked down at her arm and was glad that she didn’t have any blood, because if she did she knew for sure she’d be bleeding. And there she curled up and sobbed – until someone appeared behind her and placed a gentle hand on her shoulder. Marceline turned, “Bonnibel?”

**Notes for the Chapter:**

> Thanks to everyone who commented and left kudos for the first chapter, it means a lot to me! Thank you all for reading! - Stephanie


End file.
